In a wireless communication system, an indoor unit and an outdoor unit of a base station may be located away from each other. For example, a base transceiver station (BTS) is generally the indoor unit located inside a building, and an antenna is the outdoor unit located outside above the ground on a rooftop. Usually, a RF signal generated and outputted from the indoor unit is transmitted to the outdoor unit via a cable, jumper and the like. When a malfunction or an error occurs within the wireless communication system, it may be difficult to locate or pinpoint where the malfunction or error occurred. Often, it requires a technician to disassemble the transmission line and climb to the location of the antenna on the rooftop to do on site measurements, which may be dangerous and risky.
In addition, employing a RF remote module in a wireless communication system is becoming more popular in order to improve system performance. However, when a RF remote module experiences a problem, it is necessary to locate and evaluate the problem of the module.
At the same time, operation of a bi-polarized antenna in the wireless communication system involves determining many technical parameters such as voltage standing wave ratio (VSWR), isolation and the like. Measurement of these parameters may be important. VSWR may indicate transmission reflection characteristics of a remote unit, in particular, a passive component and an antenna unit. Polarization isolation is an important parameter for a bi-polarized antenna.
Polarization may describe the path of directional change of electrical field. The mobile communication system often uses uni-polarization antennas. Recently the bi-polarization antenna is becoming popular, which is an antenna with two cross-over antenna polarization directions. Using bi-polarization antennas may reduce the number of antennas used in a system, because one bi-polarization antenna may replace two independent uni-polarization antennas. However, it is difficult to detect the performance of the bi-polarized antenna.